This invention relates generally to articles such as training pants, diapers, feminine hygiene products, incontinence garments, material webs and the like, and more particularly to apparatus and methods for mechanically bonding and cutting such articles during assembly thereof.
Articles such as absorbent articles find widespread use as personal care products including, without limitation, diapers, children's toilet training pants, adult incontinence garments, sanitary napkins and the like, as well as surgical bandages and sponges. These articles absorb and contain body waste and are usually intended to be discarded after a limited period of use, i.e., the articles are not intended to be laundered or otherwise restored for reuse. Conventional absorbent articles comprise an absorbent body disposed between a liner, which contacts the wearer's skin, and an outer cover, which inhibits liquid body waste absorbed by the absorbent body from leaking out of the article. The liner of the absorbent article is typically liquid permeable to permit liquid body waste to pass therethrough for absorption by the absorbent body.
Conventional absorbent articles also typically include some type of fastening system for securing the absorbent article in an assembled configuration and/or for fitting the article on the wearer, such as on the wearer's waist in the case of diapers and training pants. In many such applications, the fastening system is releasable and refastenable so that the article can be temporarily removed and then refastened to the wearer.
One common form of fastening system is the so-called hook-and-loop fastening system, which comes in various forms and has both advantages and disadvantages in its application to such absorbent articles. For example, particularly when used for training pants, engageable hook and loop fasteners are secured respectively to the front and back waist regions of the article generally at overlapping side panels of the article so that the fasteners releasably engage each other to form the three dimensional shape of the article. In typical such articles, the loop fastener may form a portion of the article itself or be attached to the side panel or other component of the article. The hook fastener is generally attached to an extensible substrate (e.g., the side panel) so that it can be suitably positioned in engagement with the loop fastener material while allowing for various shapes and sizes of the intended wearers of the article.
Conventional apparatus for making absorbent articles such as children's training pants or diapers assemble the various components, such as the liner, outer cover, absorbent body, side panels (e.g., in training pants) and fastening system (e.g. a hook and loop fastening system). It is known to ultrasonically bond the fastening system to a substrate such as the liner, outer cover and/or side panels. For example a rotary ultrasonic bonding device comprising a rotary anvil roll and corresponding horn roll may be used. The anvil roll has a plurality of pins protruding therefrom about its circumference to thermally bond the fastening system to the substrate at discrete bond points.
The partially assembled article is often subsequently trimmed during manufacture, e.g., by cutting out a portion of the outer edge of the liner, outer cover and/or side panels, to provide desired form-fitting features of the article, such as the leg openings of diapers and training pants. A die cutting assembly, separate from the anvil roll and horn, is typically positioned downstream of the anvil roll for cutting the article, such as to form a tapered leg end edge of the side panels.